Known from document EP 0,591,074 A1 is a circuit breaker comprising an outer enclosure including several housings each able to receive an auxiliary block. Each auxiliary block is then removable relative to the outer enclosure. Each of the receiving housings includes electric terminals able to be connected to an auxiliary block received in the housing. Such a system allows easy customization of the circuit breaker by adding additional functions to it. The function performed by the auxiliary block is for example a signaling function, in which the auxiliary block is able to communicate the state (opened or closed) of the circuit breaker to a remote electronic device.
For safety reasons, it is necessary to prevent access to receiving housings from outside the enclosure under normal operating conditions of the circuit breaker. To that end, the outer enclosure includes a base and a cover able to cooperate to form a closed enclosure surrounding the receiving housings and the auxiliary blocks and to thus electrically isolate them from the outside.
Such a cover also makes the receiving housings and any auxiliary blocks invisible from the outside. The presence of one or more auxiliary blocks in the circuit breaker must be signaled by affixing one or more self-adhesive labels against an outer face of the enclosure of the circuit breaker. These labels bear information relative to the type and/or position of the auxiliary blocks used. The labels are placed, removed, respectively, by the operator during the placement, removal, respectively, of one or more auxiliary blocks.
However, although the placement of self-adhesive labels is a simple operation in itself, it is also a source of errors. It takes great rigor for all of the circuit breakers of a network each to be equipped with labels corresponding to the auxiliary blocks that they include. It is also necessary to update the information on the labels each time the configuration of the auxiliary blocks of the circuit breaker is changed. Furthermore, during the lifetime of a circuit breaker, the labels may be damaged, become illegible or come unstuck. It is therefore often necessary to open the cover of the outer enclosure in order to verify whether the auxiliary blocks are present, and if applicable, what type they are. For safety reasons, such an operation can only be done by an operator authorized to open the enclosure, and often requires shutting off the switching device.